PANAMA CITY, Panama - An exciting international boxing card on April 20 in Panama will mark the return of former 2-division world champion Celestino "Pelenchín" Caballero of Panama in a 12-round WBC Silver Featherweight (126 lbs - 9 st) title fight against the undefeated WBC International featherweight champion Viorel Simion (16-0, 7KO's) of Lehliu Gar***259;, Romania.